Selectively paired imaging elements for stereo images

ABSTRACT

This disclosure describes a configuration of an aerial vehicle, such as an unmanned aerial vehicle (“UAV”), that includes a plurality of cameras that may be selectively combined to form a stereo pair for use in obtaining stereo images that provide depth information corresponding to objects represented in those images. Depending on the distance between an object and the aerial vehicle, different cameras may be selected for the stereo pair based on the baseline between those cameras and a distance between the object and the aerial vehicle. For example, cameras with a small baseline (close together) may be selected to generate stereo images and depth information for an object that is close to the aerial vehicle. In comparison, cameras with a large baseline may be selected to generate stereo images and depth information for an object that is farther away from the aerial vehicle.

CROSS-REFERENCE TO PRIOR APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 15/176,734, filed on Jun. 8, 2016, which is hereby incorporated byreference in its entirety.

BACKGROUND

A digital image is a collection of pixels, typically arranged in anarray, which defines an optically formed reproduction of one or moreobjects, backgrounds or other features of a scene. In a digital image,each of the pixels represents or identifies a color or other lightcondition associated with a portion of such objects, backgrounds orfeatures. For example, a black-and-white digital image includes a singlebit for representing a light condition of the pixel in a binary fashion(e.g., either black or white), while a grayscale digital image mayrepresent the light condition in multiple bits (e.g., two to eight bitsfor defining tones of gray in terms of percentages or shares ofblack-and-white), and a color digital image may include groups of bitscorresponding to each of a plurality of base colors (e.g., red, green orblue), and the groups of bits may collectively represent a colorassociated with the pixel. One common digital image is a twenty-four bit(24-bit) color digital image, in which each of the pixels includes threechannels of eight bits each, including a first channel of eight bits fordescribing an extent of red within a pixel, a second channel of eightbits for describing an extent of green within the pixel, and a thirdchannel of eight bits for describing an extent of blue within the pixel.

A depth image, or depth map is also a collection of pixels that definesan optically formed reproduction of one or more objects, backgrounds orother features of a scene. Unlike the pixels of a digital image,however, each of the pixels of a depth image represents or identifiesnot a light condition or color of such objects, backgrounds or features,but a distance to objects, backgrounds or features. For example, a pixelof a depth image may represent a distance between a sensor of an imagingdevice that captured the depth image (e.g., a depth camera or rangesensor) and the respective object, background or feature to which thepixel corresponds.

A depth image or depth map can be determined by comparing two or moredigital images that are obtained by cameras that are separated by aknown baseline to determine a disparity between correlated pixels of thetwo or more digital images. The resolution of information for objectsrepresented in the images is often dependent on the distance between thecameras and the object and the baseline distance between the twocameras.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is set forth with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference numbers in different figures indicates similaror identical items or features.

FIG. 1 depicts a view of an unmanned aerial vehicle configuration,according to an implementation.

FIGS. 2A and 2B depict a view of a plurality of selectable imagingelements of an aerial vehicle, according to an implementation.

FIG. 3 depicts another view of a plurality of selectable imagingelements of an aerial vehicle, according to an implementation.

FIG. 4 depicts another view of a plurality of selectable imagingelements of an aerial vehicle, according to an implementation.

FIG. 5 is a flow diagram illustrating an example process for imagingelement selection, according to an implementation.

FIG. 6 is a block diagram of an illustrative implementation of anunmanned aerial vehicle control system that may be used with variousimplementations.

While implementations are described herein by way of example, thoseskilled in the art will recognize that the implementations are notlimited to the examples or drawings described. It should be understoodthat the drawings and detailed description thereto are not intended tolimit implementations to the particular form disclosed but, on thecontrary, the intention is to cover all modifications, equivalents andalternatives falling within the spirit and scope as defined by theappended claims. The headings used herein are for organizationalpurposes only and are not meant to be used to limit the scope of thedescription or the claims. As used throughout this application, the word“may” is used in a permissive sense (i.e., meaning having the potentialto), rather than the mandatory sense (i.e., meaning must). Similarly,the words “include,” “including,” and “includes” mean “including, butnot limited to.” Additionally, as used herein, the term “coupled” mayrefer to two or more components connected together, whether thatconnection is permanent (e.g., welded) or temporary (e.g., bolted),direct or indirect (i.e., through an intermediary), mechanical,chemical, optical, or electrical. Furthermore, as used herein,“horizontal” flight refers to flight traveling in a directionsubstantially parallel to the ground (i.e., sea level), and that“vertical” flight refers to flight traveling substantially radiallyoutward from the earth's center. It should be understood by those havingordinary skill that trajectories may include components of both“horizontal” and “vertical” flight vectors.

DETAILED DESCRIPTION

This disclosure describes a configuration of an aerial vehicle, such asan unmanned aerial vehicle (“UAV”), that includes a plurality of camerasthat may be selectively combined to form a stereo pair for use inobtaining images that may be processed together to provide depthinformation corresponding to objects represented in those images.Depending on the distance between an object and the aerial vehicle,different combinations of cameras may be selected for the stereo pairbased on a baseline distance between those cameras. For example, cameraswith a small baseline distance (close together) may be selected togenerate images that are compared to determine depth information for anobject that is close to the aerial vehicle. In comparison, cameras witha large baseline distance may be selected to generate images that arecompared to determine depth information for an object that is fartheraway from the aerial vehicle.

FIG. 1 illustrates a view of an aerial vehicle, in this instance a UAV100, according to an implementation. As illustrated, the UAV 100includes a perimeter frame 104 that includes a front wing 120, a lowerrear wing 124, an upper rear wing 122, and two horizontal side rails130-1, 130-2. The horizontal side rails 130 are coupled to opposing endsof the front wing 120 and opposing ends of the upper rear wing 122 andlower rear wing 124. In some implementations, the coupling may be with acorner junction, such as the front left corner junction 131-1, the frontright corner junction 131-2, the rear left corner junction 131-3, andthe rear right corner junction 131-4. In such an example, the cornerjunctions are also part of the perimeter frame 104.

The components of the perimeter frame 104, such as the front wing 120,lower rear wing 124, upper rear wing 122, side rails 130-1, 130-2, andcorner junctions 131 may be formed of any one or more suitablematerials, such as graphite, carbon fiber, aluminum, titanium, etc., orany combination thereof. In the illustrated example, the components ofthe perimeter frame 104 of the UAV 100 are each formed of carbon fiberand joined at the corners using corner junctions 131. The components ofthe perimeter frame 104 may be coupled using a variety of techniques.For example, if the components of the perimeter frame 104 are carbonfiber, they may be fitted together and joined using secondary bonding, atechnique known to those of skill in the art. In other implementations,the components of the perimeter frame 104 may be affixed with one ormore attachment mechanisms, such as screws, rivets, latches,quarter-turn fasteners, etc., or otherwise secured together in apermanent or removable manner.

The front wing 120, lower rear wing 124, and upper rear wing 122 arepositioned in a tri-wing configuration and each wing provides lift tothe UAV 100 when the UAV is moving in a direction that includes ahorizontal component. For example, the wings may each have an airfoilshape that causes lift due to the airflow passing over the wings duringhorizontal flight.

Opposing ends of the front wing 120 may be coupled to a corner junction131, such as the front left corner junction 131-1 and front right cornerjunction 131-2. In some implementations, the front wing may include oneor more flaps 127 or ailerons, that may be used to adjust the pitch,yaw, and/or roll of the UAV 100 alone or in combination with the liftingmotors 106, lifting propellers 102, thrusting motors 110, thrustingpropellers 112, and/or other flaps on the rear wings, discussed below.In some implementations, the flaps 127 may also be used as a protectiveshroud to further hinder access to the lifting propellers 102 by objectsexternal to the UAV 100. For example, when the UAV 100 is moving in avertical direction or hovering, the flaps 127 may be extended toincrease the height of the protective barrier around a portion of thelifting propellers 102.

In some implementations, the front wing 120 may include two or morepairs of flaps 127, as illustrated in FIG. 1. In other implementations,for example if there is no front thrusting motor 110-1, the front wing120 may only include a single flap 127 that extends substantially thelength of the front wing 120. If the front wing 120 does not includeflaps 127, the lifting motors 106 and lifting propellers 102, thrustingmotors 110, thrusting propellers 112 and/or flaps of the rear wings maybe utilized to control the pitch, yaw, and/or roll of the UAV 100 duringflight.

Opposing ends of the lower rear wing 124 may be coupled to a cornerjunction 131, such as the rear left corner junction 131-3 and rear rightcorner junction 131-4. In some implementations, the lower rear wing mayinclude one or more flaps 123 or ailerons, that may be used to adjustthe pitch, yaw and/or roll of the UAV 100 alone or in combination withthe lifting motors 106, lifting propellers 102, thrusting motors 110,thrusting propellers 112, and/or the flaps 127 of the front wing. Insome implementations, the flaps 123 may also be used as a protectiveshroud to further hinder access to the lifting propellers 102 by objectsexternal to the UAV 100. For example, when the UAV 100 is moving in avertical direction or hovering, the flaps 123 may be extended, similarto the extending of the front flaps 127 of the front wing 120.

In some implementations, the rear wing 124 may include two or more flaps123, as illustrated in FIG. 1 or two or more pairs of flaps,respectively. In other implementations, for example if there is no rearthrusting motor 110-2 mounted to the lower rear wing, the rear wing 124may only include a single flap 123 that extends substantially the lengthof the lower rear wing 124. In other implementations, if the lower rearwing includes two thrusting motors, the lower rear wing may beconfigured to include three flaps 123, one on either end of the lowerrear wing 124, and one between the two thrusting motors mounted to thelower rear wing 124.

Opposing ends of the upper rear wing 122 may be coupled to a cornerjunction 131, such as the rear left corner junction 131-3 and rear rightcorner junction 131-4. In some implementations, like the lower rearwing, the upper rear wing 122 may include one or more flaps (not shown)or ailerons, that may be used to adjust the pitch, yaw and/or roll ofthe UAV 100 alone or in combination with the lifting motors 106, liftingpropellers 102, thrusting motors 110, thrusting propellers 112, and/orother flaps of other wings. In some implementations, the flaps may alsobe used as a protective shroud to further hinder access to the liftingpropellers 102 by objects external to the UAV 100. For example, when theUAV 100 is moving in a vertical direction or hovering, the flaps may beextended, similar to the extending of the front flaps 127 of the frontwing 120 or the flaps 123 of the lower rear wing.

The front wing 120, lower rear wing 124, and upper rear wing 122 may bepositioned and sized proportionally to provide stability to the UAVwhile the UAV 100 is moving in a direction that includes a horizontalcomponent. For example, the lower rear wing 124 and the upper rear wing122 are stacked vertically such that the vertical lift vectors generatedby each of the lower rear wing 124 and upper rear wing 122 are closetogether, which may be destabilizing during horizontal flight. Incomparison, the front wing 120 is separated from the rear wingslongitudinally such that the vertical lift vector generated by the frontwing 120 acts together with the vertical lift vectors of the lower rearwing 124 and the upper rear wing 122, providing efficiency,stabilization and control.

In some implementations, to further increase the stability and controlof the UAV 100, one or more winglets 121, or stabilizer arms, may alsobe coupled to and included as part of the perimeter frame 104. In theexample illustrated with respect to FIG. 1, there are two front winglets121-1 and 121-2 mounted to the underneath side of the front left cornerjunction 131-1 and the front right corner junction 131-2, respectively.The winglets 121 extend in a downward direction approximatelyperpendicular to the front wing 120 and side rails 130. Likewise, thetwo rear corner junctions 131-3, 131-4 are also formed and operate aswinglets providing additional stability and control to the UAV 100 whenthe UAV 100 is moving in a direction that includes a horizontalcomponent.

The winglets 121 and the rear corner junctions 131 may have dimensionsthat are proportional to the length, width, and height of the UAV 100and may be positioned based on the approximate center of gravity of theUAV 100 to provide stability and control to the UAV 100 duringhorizontal flight. For example, in one implementation, the UAV 100 maybe approximately 64.75 inches long from the front of the UAV 100 to therear of the UAV 100 and approximately 60.00 inches wide. In such aconfiguration, the front wing 120 has dimensions of approximately 60.00inches by approximately 7.87 inches. The lower rear wing 124 hasdimensions of approximately 60.00 inches by approximately 9.14 inches.The upper rear wing 122 has dimensions of approximately 60.00 inches byapproximately 5.47 inches. The vertical separation between the lowerrear wing and the upper rear wing is approximately 21.65 inches. Thewinglets 121 are approximately 6.40 inches wide at the corner junctionwith the perimeter frame of the UAV, approximately 5.91 inches wide atthe opposing end of the winglet and approximately 23.62 inches long. Therear corner junctions 131-3, 131-4 are approximately 9.14 inches wide atthe end that couples with the lower rear wing 124, approximately 8.04inches wide at the opposing end, and approximately 21.65 inches long.The overall weight of the UAV 100 is approximately 50.00 pounds.

Coupled to the interior of the perimeter frame 104 is a central frame107. The central frame 107 includes a hub 108 and motor arms 105 thatextend from the hub 108 and couple to the interior of the perimeterframe 104. In this example, there is a single hub 108 and four motorarms 105-1, 105-2, 105-3, and 105-4. Each of the motor arms 105 extendfrom approximately a corner of the hub 108 and couple or terminate intoa respective interior corner of the perimeter frame. In someimplementations, each motor arm 105 may couple into a corner junction131 of the perimeter frame 104. Like the perimeter frame 104, thecentral frame 107 may be formed of any suitable material, such asgraphite, carbon fiber, aluminum, titanium, etc., or any combinationthereof. In this example, the central frame 107 is formed of carbonfiber and joined at the corners of the perimeter frame 104 at the cornerjunctions 131. Joining of the central frame 107 to the perimeter frame104 may be done using any one or more of the techniques discussed abovefor joining the components of the perimeter frame 104.

Lifting motors 106 are coupled at approximately a center of each motorarm 105 so that the lifting motor 106 and corresponding liftingpropeller 102 are within the substantially rectangular shape of theperimeter frame 104. In one implementation, the lifting motors 106 aremounted to an underneath or bottom side of each motor arm 105 in adownward direction so that the propeller shaft of the lifting motor thatmounts to the lifting propeller 102 is facing downward. In otherimplementations, as illustrated in FIG. 1, the lifting motors 106 may bemounted to a top of the motor arms 105 in an upward direction so thatthe propeller shaft of the lifting motor that mounts to the liftingpropeller 102 is facing upward. In this example, there are four liftingmotors 106-1, 106-2, 106-3, 106-4, each mounted to an upper side of arespective motor arm 105-1, 105-2, 105-3, and 105-4.

In some implementations, multiple lifting motors may be coupled to eachmotor arm 105. For example, while FIG. 1 illustrates a quad-copterconfiguration with each lifting motor mounted to a top of each motorarm, a similar configuration may be utilized for an octo-copter. Forexample, in addition to mounting a motor 106 to an upper side of eachmotor arm 105, another lifting motor may also be mounted to anunderneath side of each motor arm 105 and oriented in a downwarddirection. In another implementation, the central frame may have adifferent configuration, such as additional motor arms. For example,eight motor arms may extend in different directions and a lifting motormay be mounted to each motor arm.

The lifting motors may be any form of motor capable of generating enoughrotational speed with the lifting propellers 102 to lift the UAV 100 andany engaged payload, thereby enabling aerial transport of the payload.

Mounted to each lifting motor 106 is a lifting propeller 102. Thelifting propellers 102 may be any form of propeller (e.g., graphite,carbon fiber) and of a size sufficient to lift the UAV 100 and anypayload engaged by the UAV 100 so that the UAV 100 can navigate throughthe air, for example, to deliver a payload to a delivery location. Forexample, the lifting propellers 102 may each be carbon fiber propellershaving a dimension or diameter of twenty-four inches. While theillustration of FIG. 1 shows the lifting propellers 102 all of a samesize, in some implementations, one or more of the lifting propellers 102may be different sizes and/or dimensions. Likewise, while this exampleincludes four lifting propellers 102-1, 102-2, 102-3, 102-4, in otherimplementations, more or fewer propellers may be utilized as liftingpropellers 102. Likewise, in some implementations, the liftingpropellers 102 may be positioned at different locations on the UAV 100.In addition, alternative methods of propulsion may be utilized as“motors” in implementations described herein. For example, fans, jets,turbojets, turbo fans, jet engines, internal combustion engines, and thelike may be used (either with propellers or other devices) to providelift for the UAV.

In addition to the lifting motors 106 and lifting propellers 102, theUAV 100 may also include one or more thrusting motors 110 andcorresponding thrusting propellers 112. The thrusting motors andthrusting propellers may be the same or different than the liftingmotors 106 and lifting propellers 102. For example, in someimplementations, the thrusting propellers may be formed of carbon fiberand be approximately eighteen inches long. In other implementations, thethrusting motors may utilize other forms of propulsion to propel theUAV. For example, fans, jets, turbojets, turbo fans, jet engines,internal combustion engines, and the like may be used (either withpropellers or with other devices) as the thrusting motors.

The thrusting motors and thrusting propellers may be oriented atapproximately ninety degrees with respect to the perimeter frame 104 andcentral frame 107 of the UAV 100 and utilized to increase the efficiencyof flight that includes a horizontal component. For example, when theUAV 100 is traveling in a direction that includes a horizontalcomponent, the thrusting motors may be engaged to provide a horizontalthrust force via the thrusting propellers to propel the UAV 100horizontally. As a result, the speed and power utilized by the liftingmotors 106 may be reduced. Alternatively, in selected implementations,the thrusting motors may be oriented at an angle greater or less thanninety degrees with respect to the perimeter frame 104 and the centralframe 107 to provide a combination of thrust and lift.

In the example illustrated in FIG. 1, the UAV 100 includes two thrustingmotors 110-1, 110-2 and corresponding thrusting propellers 112-1, 112-2.Specifically, in the illustrated example, there is a front thrustingmotor 110-1 coupled to and positioned near an approximate mid-point ofthe front wing 120. The front thrusting motor 110-1 is oriented suchthat the corresponding thrusting propeller 112-1 is positioned insidethe perimeter frame 104. The second thrusting motor is coupled to andpositioned near an approximate mid-point of the lower rear wing 124. Therear thrusting motor 110-2 is oriented such that the correspondingthrusting propeller 112-2 is positioned inside the perimeter frame 104.

While the example illustrated in FIG. 1 illustrates the UAV with twothrusting motors 110 and corresponding thrusting propellers 112, inother implementations, there may be fewer or additional thrusting motorsand corresponding thrusting propellers. For example, in someimplementations, the UAV 100 may only include a single rear thrustingmotor 110 and corresponding thrusting propeller 112. In anotherimplementation, there may be two thrusting motors and correspondingthrusting propellers mounted to the lower rear wing 124. In such aconfiguration, the front thrusting motor 110-1 may be included oromitted from the UAV 100. Likewise, while the example illustrated inFIG. 1 shows the thrusting motors oriented to position the thrustingpropellers inside the perimeter frame 104, in other implementations, oneor more of the thrusting motors 110 may be oriented such that thecorresponding thrusting propeller 112 is oriented outside of theprotective frame 104.

The perimeter frame 104 provides safety for objects foreign to the UAV100 by inhibiting access to the lifting propellers 102 from the side ofthe UAV 100, provides protection to the UAV 100, and increases thestructural integrity of the UAV 100. For example, if the UAV 100 istraveling horizontally and collides with a foreign object (e.g., wall,building), the impact between the UAV 100 and the foreign object will bewith the perimeter frame 104, rather than a propeller. Likewise, becausethe frame is interconnected with the central frame 107, the forces fromthe impact are dissipated across both the perimeter frame 104 and thecentral frame 107.

The perimeter frame 104 also provides a surface upon which one or morecomponents of the UAV 100 may be mounted. Alternatively, or in additionthereto, one or more components of the UAV may be mounted or positionedwithin the cavity of the portions of the perimeter frame 104. Forexample, one or more antennas may be mounted on or in the front wing120. The antennas may be used to transmit and/or receive wirelesscommunications. For example, the antennas may be utilized for Wi-Fi,satellite, near field communication (“NFC”), cellular communication, orany other form of wireless communication. Other components, such asimaging elements (e.g., cameras), time of flight sensors,accelerometers, inclinometers, distance-determining elements, gimbals,Global Positioning System (GPS) receiver/transmitter, radars,illumination elements, speakers, and/or any other component of the UAV100 or the aerial vehicle control system (discussed below), etc., maylikewise be mounted to or in the perimeter frame 104. Likewise,identification or reflective identifiers may be mounted to the perimeterframe 104 to aid in the identification of the UAV 100.

In some implementations, as discussed below, multiple imaging elements150, such as digital still cameras, red, green, blue (RGB) cameras,video cameras, thermographic cameras, etc., may be mounted to and spacedabout the frame of the UAV 100. Likewise, one or more distancedetermining elements 151 may be coupled to the frame of the aerialvehicle. Any type of distance determining element may be utilized,including, but not limited to, a time-of-flight sensor, range finder,SONAR, LIDAR, etc.

The imaging elements 150 may be arranged such that at least a portion ofthe field of view of multiple imaging elements overlap. As discussedfurther below, the imaging elements 150 may communicate with and becontrolled by an imaging element selection controller that dynamicallyselects two or more imaging elements as a stereo pair or imaging elementpair. The selected combination of imaging elements is used to obtainimages of objects in the common field of view for those selected imagingelements and the obtained images are processed to generate depthinformation, such as disparity and displacement, for objects representedin the common field of view.

As illustrated, the imaging elements 150 may be affixed to any portionof the frame of the UAV 100. For example, a first group of imagingelements 150 may be arranged along the front of the front wing 120 andoriented such that the field of view of those imaging elements at leastpartially overlap (i.e., are common). As another example, a second groupof imaging elements 150 may be arranged along the underneath or lowerside of the side rail 130-1 and oriented such that the field of view ofthose imaging elements is at least partially common. As will beappreciated, any number of imaging elements may be included in a groupor set of imaging elements with overlapping fields of view and anynumber of sets of imaging elements may be arranged along the UAV 100.The imaging elements of each set of imaging elements 150 may becontrolled by one or more imaging element selection controllers, asdiscussed further below.

In some implementations, the perimeter frame 104 may also include apermeable material (e.g., mesh, screen) that extends over the top and/orlower surface of the perimeter frame 104 enclosing the central frame,lifting motors, and/or lifting propellers.

An aerial vehicle control system 114 is also mounted to the centralframe 107. In this example, the aerial vehicle control system 114 ismounted to the hub 108 and is enclosed in a protective barrier. Theprotective barrier may provide the control system 114 weather protectionso that the UAV 100 may operate in rain and/or snow without disruptingthe control system 114. In some implementations, the protective barriermay have an aerodynamic shape to reduce drag when the UAV is moving in adirection that includes a horizontal component. The protective barriermay be formed of any materials including, but not limited to,graphite-epoxy, Kevlar, and/or fiberglass. In some implementations,multiple materials may be utilized. For example, Kevlar may be utilizedin areas where signals need to be transmitted and/or received.

Likewise, the UAV 100 includes one or more power modules 153. In someimplementations, the power modules 153 may be positioned inside thecavity of the side rails 130-1, 130-2. In other implementations, thepower modules 153 may be mounted or positioned at other locations of theUAV. The power modules 153 for the UAV may be in the form of batterypower, solar power, gas power, super capacitor, fuel cell, alternativepower generation source, or a combination thereof. For example, thepower modules 153 may each be a 6000 mAh lithium-ion polymer battery, orpolymer lithium ion (Li-poly, Li-Pol, LiPo, LIP, PLI or Lip) battery.The power module(s) are coupled to and provide power for the aerialvehicle control system 114, the lifting motors 106, the thrusting motors110, the imaging elements 150, and the payload engagement mechanism 154.

In some implementations, one or more of the power modules 153 may beconfigured such that it can be autonomously removed and/or replaced withanother power module while the UAV is landed or in flight. For example,when the UAV lands at a location, the UAV may engage with a chargingmember at the location that will recharge the power module.

As mentioned above, the UAV 100 may also include a payload engagementmechanism 154. The payload engagement mechanism 154 may be configured toengage and disengage items and/or containers that hold items (payload).In this example, the payload engagement mechanism 154 is positionedbeneath and coupled to the hub 108 of the frame 104 of the UAV 100. Thepayload engagement mechanism 154 may be of any size sufficient tosecurely engage and disengage a payload. In other implementations, thepayload engagement mechanism 154 may operate as the container in whichit contains item(s). The payload engagement mechanism 154 communicateswith (via wired or wireless communication) and is controlled by theaerial vehicle control system 114. Example payload engagement mechanismsare described in co-pending patent application Ser. No. 14/502,707,filed Sep. 30, 2014, titled “UNMANNED AERIAL VEHICLE DELIVERY SYSTEM,”the subject matter of which is incorporated by reference herein in itsentirety.

FIGS. 2A and 2B depict a view of a plurality of selectable imagingelements 250, or cameras, of an aerial vehicle, such as a UAV, accordingto an implementation. In this example, there are seven imaging elementsarranged along a portion of a frame 210 of an aerial vehicle. As will beappreciated, any number and arrangement of imaging elements may beutilized with the implementations described herein. Likewise, anyspacing configuration may be utilized. The only constraint is that thefield of view of each imaging element 250 of the set or plurality ofimaging elements at least partially overlap with the field of view of atleast one other imaging element of the set. In some implementations, theconfiguration and spacing of imaging elements 250 may be such that thefield of view of each imaging element at least partially overlaps withthe field of view of at least two other imaging elements of theplurality of imaging element. In still other implementations, theconfiguration and spacing may be such that at least a portion of thefield of view of each imaging element overlaps with the field of view ofeach of the other imaging elements of the plurality of imaging elements.

In the illustrated example, the placement and spacing of the imagingelements 250-1, 250-2, 250-3, 250-4, 250-5, 250-6, and 250-7 is suchthat no two baseline distances (b₁, b₂, b₃, b₄, b₅, b₆, b₇, b₈, b₉, b₁₀,b₁₁, b₁₂, b₁₃, b₁₄, b₁₅, b₁₆, b₁₇, b₁₈, b₁₉, b₂₀, and b₂₁,) are thesame. In other configurations, some or all of the baseline distances maybe approximately the same distance.

By spacing the imaging elements 250 such that each potential pair ofimaging elements have a different baseline, the number of differentavailable baseline distances increases. For example, if all baselinedistances are different, the number of available baselines is equal tothe binomial coefficient:

$\left( \frac{n}{k} \right) = \frac{n!}{k{!{\left( {n - k} \right)!}}}$where n is the quantity of imaging elements and k is the number ofimaging elements selected for the combination (e.g., two). In theexample illustrated in FIGS. 2A-2B, there are seven imaging elements (n)250-1, 250-2, 250-3, 250-4, 250-5, 250-6, and 250-7, which, if taken incombinations of two (k), results in twenty-one different combinations.By arranging the position of the imaging elements such that all thebaseline distances are different, the imaging element selectioncontroller will have twenty-one different baselines and imaging elementcombinations from which to choose. Likewise, by providing the ability toswitch between combinations of imaging elements, regardless of whetherthe baseline distances are the same or different, redundancy isincreased. For example, if one of the imaging elements becomesinoperable (e.g., damaged), depth information may be obtained from adifferent combination of imaging elements of the aerial vehicle.

As is known in the art, a smaller baseline is typically preferred andprovides better imaging results and depth information for objects thatare closer to the imaging elements. Likewise, a larger baseline istypically preferred and provides better imaging results and depthinformation for objects that are farther from the imaging elements. Insome implementations, the imaging element selection controller mayutilize a ratio to determine which combination of imaging elements toselect to obtain images that are compared to generate depth informationfor an object that is a distance from the UAV. For example, the imagingelement selection controller may utilize a 1:30 ratio to select acombination of imaging elements based on the approximate distancebetween an object and the UAV. For example, using a 1:30 ratio, if thedetected object is approximately 15 meters from the UAV, imagingelements having a baseline closest to 0.5 meters will be selected as thestereo pair of imaging elements. For example, imaging elements 250-2 and250-4 may be selected if the baseline distance b₁₀ is approximately 0.5meters.

In other implementations, a primary distance, middle distance betweenthe different combinations, or multiple groups of combinations may bemonitored to detect objects within a distance from the aerial vehicle.Upon object detection, it may be determined which combination of imagingelements provide the best depth information, such as disparity betweenpixels of the compared images. In some implementations, distance betweenthe UAV and the object may be estimated over a series of images fromdifferent combinations of imaging elements. For example, if an object isrepresented in a first stereo pair that has a small baseline but notrepresented in a second stereo pair that has a larger baseline, it canbe determined that the object is within a defined distance that is lessthan distance between the UAV and the common field of view of the secondstereo pair. As another example, if the object is represented by a fewpixels in a first combination of imaging elements that have a smallbaseline, but is represented by a much larger quantity of pixels in asecond combination of imaging elements that have a large baseline, itcan be assumed that the object is farther away from the UAV.

Regardless of the technique used to select a combination of imagingelements, as the distance between the object and the UAV changes, theimaging element selection controller may alter one or both of theimaging elements of the stereo pair. For example, if the object movescloser to the UAV, the imaging element selection controller may selectimaging element 250-4 and 250-5 because the baseline distance b₁₃ isless than the baseline distance b₁₀. The smaller baseline distance b₁₃will provide better disparity information for a closer object. Likewise,if the distance between the object and the UAV continues to decrease,the imaging element selection controller may keep imaging element 250-5and select imaging element 250-6 as the stereo pair because the baselinedistance b₁₅ is less than the baseline distance b₁₃.

In some implementations, the imaging element selection controller mayobtain images and determine depth information from multiple combinationsof imaging elements and combine the depth information. For example,depth information generated from images provided by the combination ofimaging elements 250-1 and 250-2 may be combined with depth informationgenerated from images provided by the combination of imaging elements250-3 and 250-6. The different baseline distances provide differentlevels of resolution for the depth information and the combination ofdepth information may increase the overall accuracy of the depthinformation.

In some implementations, if an error or inaccuracy in the depthinformation is detected from a first combination of imaging elements, adifferent combination of imaging elements may be selected. For example,images from some combinations of imaging elements may not produceaccurate depth information because, for example, the field of view isoccluded, affected by light (e.g., sunlight), etc. In such animplementation, a different combination of imaging elements, ordifferent sets of combinations of imaging elements may be selected andused to generate depth information.

In some instances, the angle of the baseline between combinations ofimaging elements may also be altered. For example, as illustrated inFIG. 2A, the first six imaging elements 250-1-250-6 are alignedhorizontally along the portion 210 of the UAV. As such, the baselinedistance between each combination of the imaging elements 250-1-250-6 ishas approximately a same angle or alignment. However, as illustrated inFIG. 2B, selecting a combination of imaging elements that includesimaging element 250-7 results in a baseline that extends along adifferent angle or orientation. For example, the alignment of each ofthe baseline distances b₁₆-b₂₁ is different than each other anddifferent than each of the baseline distances b₁-b₁₅.

As will be appreciated, other forms of selection may be utilized todetermine which combination of imaging elements to select for imaging anobject and generating depth information. Likewise, in someimplementations, the resultant depth information may be analyzed toassess whether the combined results are potentially representative ofthe object. As still another example, in some implementations, some orall of the imaging elements 250 may obtain images and those images maybe stored in a data store of the UAV. The imaging element selectioncontroller may then determine which imaging elements to utilize as astereo pair and select the stored images obtained by those imagingelements for use in generating depth information.

FIG. 3 depicts another view of a plurality of selectable imagingelements of an aerial vehicle, according to an implementation.Continuing with the example illustrated in FIG. 2A, FIG. 3 illustratesthe six imaging elements 350-1, 350-2, 350-3, 350-4, 350-5, and 350-6arranged along portion 311 of an aerial vehicle. As illustrated, each ofthe imaging elements 350 are coupled to, communicate with and arecontrolled by an imaging element selection controller 310. Asillustrated, each of the imaging elements have a field of view 360-1,360-2, 360-3, 360-4, 360-5, and 360-6. Those fields of view partiallyoverlap forming common fields of view. For example, field of view 360-1of imaging element 350-1 partially overlaps with field of view 360-2 ofimaging element 350-2 to form a common field of view 366. Likewise,field of view 360-5 of imaging element 350-5 partially overlaps withfield of view 360-6 of imaging element 350-6 to form common field ofview 368.

The imaging element selection controller may determine which imagingelements to activate as a stereo pair of imaging elements. For example,one or more combinations of imaging elements, such as imaging elements350-1 and 350-2, and/or 350-5 and 350-6 may be used to initially monitorfor objects. If an object 370 is detected, an approximate distancebetween the UAV and the object is determined.

For example, if an object 370 is detected in the common field of view366 of imaging elements 35-1 and 350-2 but no or limited disparity orother depth information is determinable from a processing of the imagesgenerated by each of imaging elements 350-1 and 350-2, it may bedetermined that the object is at a far distance from the UAV. In such anexample, the imaging element selection controller may select anothercombination of imaging elements, such as imaging elements 350-1 and350-6 and process images from those imaging elements to determine ifdepth information for the object is obtainable from the processedimages. If depth information still cannot be determined, it may bedecided that the object is beyond a distance of potential interest tothe UAV. However, if depth information is determined from a processingof images generated by imaging elements 350-1 and 350-2, the object maybe monitored and additional depth information obtained.

In some implementations, multiple stereo pairs may be activated by theimaging element selection controller and images from those stereo pairsprocessed in parallel to determine which combination of imaging elementsprovides the best resolution of depth information for the detectedobject. For example, in addition to selecting imaging elements 350-1 and350-6 as a stereo pair of imaging elements, imaging elements 360-3 and360-4 may also be activated as a stereo pair of imaging elements. Insuch an implementation, the depth information generated from images ofthe two stereo pairs may be combined to provide greater resolutionregarding the distance of the object from the aerial vehicle. Likewise,by monitoring the distance of the object with two stereo pairs that havedifferent baseline distances and different common fields of view, if theobject moves out of a common field of view of one of the stereo pairs itmay remain in the common field of view of the second stereo pair.

For example, the field of view 360-1 of imaging element 350-1 overlapswith the field of view 360-6 of imaging element 350-6, as illustrated byoverlapping or common field of view 362. Likewise, the object 370 ispositioned in the common field of view 362. In a similar manner, thefield of view 360-3 of imaging element 350-3 overlaps with the field ofview 360-4 of imaging element 350-4, as illustrated by overlapping orcommon field of view 364. The object 370 is also positioned in thecommon field of view 364. If the object, or the UAV, moves such that theobject 370 is closer to the UAV, the object 370 may exit the commonfield of view 362 but remain in the common field of view 364.

When the imaging element selection controller 310 selects a combinationof imaging elements and receives or obtains images obtained by thoseimaging elements, the overlapping portions of those images are alignedbased on a pixel relationship that is established when the imagingelements are calibrated, as is known in the art. The alignment of thepixel information and the known baseline information between theselected imaging elements are used to determine depth information forobjects represented in both images. In the present implementations,multiple cameras are calibrated as the different potential combinationswith the different baselines. The imaging element selection controllermay then select the appropriate combination of imaging elements as thestereo pair for obtaining images that are used to form depthinformation.

FIG. 4 depicts another view of a plurality of selectable cameras of anaerial vehicle, according to an implementation. In this example, twopairs of stereo cameras are coupled to a portion 411 of an aerialvehicle. In a first mode of operation, the first stereo cameraarrangement, which includes imaging elements 450-1 and 450-2 provideimages to stereo controller 410-1 that processes the images. Likewise,the second stereo camera arrangement, which includes imaging elements450-3 and 450-4 provides images to stereo controller 410-2 thatprocesses the images. The images processed from the two pairs of stereocameras may be analyzed to determine if an object is detected. Forexample, a change in pixel values, or depth information may beindicative of a presence of an object. Alternatively, or in additionthereto, one or more image processing algorithms may be utilized todetect objects represented in the images.

If an object is detected at a farther distance from the aerial vehicle,the imaging element selection controller 412 may use an imaging elementfrom each of the stereo pairs, such as imaging element 450-2 and imagingelement 450-3 to dynamically generate a third stereo pair of imagingelements that may be used to generate imaging information for theobject. For example, if the object is in the common field of view 464 ofimaging element 450-2 and imaging element 450-3, the imaging elementselection controller 412 may obtain images from those imaging elements450-2, 450-3 and process those images to generate depth information forobjects in that common field of view 464.

While FIGS. 2A-4 illustrate different configurations of a plurality ofimaging elements that may be selectively paired by an imaging elementselection controller to generate depth information based on differentbaseline distances, it will be appreciated that any number, combination,and/or spacing of imaging elements may be utilized with theimplementations discussed herein. Likewise, while the discussionsdescribe pairing two imaging elements, in some implementations, theimagining element selection controller may combine images from more thantwo imaging elements. Likewise, any number of imaging elements may beactivated to obtain images at approximately the same time. The imagingelement selection controller may then process different combinations ofthose images to generate different sets of depth information for anobject represented on those images. The different sets of depthinformation may then be combined to provide increased resolution for thedepth information. For example, if three imaging elements are activated,such as imaging elements 350-2, 350-3, 350-4 and 350-6, and each ofthose imaging elements generate an image at approximately the same time,the imaging element selection controller may generate six different setsof depth information, each set based on a different combination andbaseline of imaging elements. Specifically, the imaging elementselection controller may generate a first set of depth information basedon images generated by imaging elements 350-2 and 350-3, a second set ofdepth information based on images generated by imaging elements 350-2and 350-4, a third set of depth information based on images generated byimaging elements 350-2 and 350-6, a fourth set of depth informationbased on images generated by imaging elements 350-3 and 350-4, a fifthset of depth information based on images generated by imaging elements350-3 and 350-6, and a sixth set of depth information based on imagesgenerated by imaging elements 350-4 and 350-6.

Those sets of depth information may then be combined to provide a higherresolution of depth information. Alternatively, or in addition thereto,the different sets of depth information may be compared to select acombination of imaging elements for continued image generation formonitoring the position of the object with respect to the UAV.

FIG. 5 is a flow diagram illustrating an example process for imagingelement selection, according to an implementation. The process of FIG. 5and each of the other processes and sub-processes discussed herein maybe implemented in hardware, software, or a combination thereof. In thecontext of software, the described operations representcomputer-executable instructions stored on one or more computer-readablemedia that, when executed by the one or more processors, perform therecited operations. Generally, computer-executable instructions includeroutines, programs, objects, components, data structures, and the likethat perform particular functions or implement particular abstract datatypes.

The computer-readable media may include non-transitory computer-readablestorage media, which may include hard drives, floppy diskettes, opticaldisks, CD-ROMs, DVDs, read-only memories (ROMs), random access memories(RAMs), EPROMs, EEPROMs, flash memory, magnetic or optical cards,solid-state memory devices, or other types of storage media suitable forstoring electronic instructions. In addition, in some implementationsthe computer-readable media may include a transitory computer-readablesignal (in compressed or uncompressed form). Examples ofcomputer-readable signals, whether modulated using a carrier or not,include, but are not limited to, signals that a computer system hostingor running a computer program can be configured to access, includingsignals downloaded through the Internet or other networks. Finally, theorder in which the operations are described is not intended to beconstrued as a limitation, and any number of the described operationscan be combined in any order and/or in parallel to implement theprocess.

The example process 500 begins by monitoring for an object using a firststereo pair of imaging elements, as in 502. For example, the process mayutilize a pair of imaging elements having a smallest baseline and/or alargest common field of view for initial detection of objects.Alternatively, there may be a primary or preferred distance that is tobe monitored and a pair of imaging elements selected that provide thehighest resolution for objects detected at that primary or preferreddistance. As discussed above, images may be obtained using the pair ofimaging elements and processed to detect objects represented in thecombined images.

In addition, or as an alternative to using images from a first pair ofimaging elements to detect an object, a distance determining element,such as a range finder, time-of-flight sensor, SONAR, LIDAR, and/orother like component, may be used to detect a presence of an objectwithin a distance of an aerial vehicle. As still another example, ratherthan using images from a pair of cameras, images from a single cameramay be obtained and processed to determine a presence of a potentialobject. For example, pixel values may be compared between images todetect changes in the field of view that may be representative of anobject. If a potential object is detected, additional processing, using,for example, a pair of imaging elements and/or a distance determiningelement, as discussed above, may be utilized to determine a presence ofan object.

Based on the monitoring, a determination is made as to whether an objecthas been detected, as in 504. If it is determined that an object has notbeen detected, the example process 500 returns to block 502 andcontinues. If it is determined that an object has been detected, anapproximate distance between the object and the aerial vehicle isdetermined, as in 506. For example, the stereo imaging information andthe known baseline may be utilized to determine an approximate distancebetween the object and the aerial vehicle. Likewise, the distancedetermined by a distance determining element may be utilized as theapproximate distance.

Based on the determined approximate distance, a combination of imagingelements is selected for use in obtaining images of the object that areused to generate depth information about the object. The selection maybe made based at least in part on the determined approximate distanceand the baselines of the available combinations of imaging elements. Forexample, a ratio, such as a 1:30 ratio may be utilized and a combinationof imaging elements selected that is closest to the ratio based on thedetermined approximate distance between the object and the aerialvehicle. Alternatively, multiple combinations of imaging elements may beselected and disparity information generated. The combination of imagingelements with the greatest disparity information may be selected tomonitor the object. Other techniques may likewise by utilized to selecta combination of imaging elements.

The example process 500 may continue as the distance between the objectand the aerial vehicle alters and/or during any operation of the aerialvehicle. For example, if the distance between the aerial vehicle and theobject changes (increases or decreases) the selected combination ofimaging elements may be changed with each completion of the exampleprocess 500. For example, if the distance between the aerial vehicle andthe object increases, one or more of the imaging elements may be changedsuch that the baseline distance between the selected combination ofimaging elements corresponds with a ratio and/or other criteria of theexample process 500, based on the updated distance between the objectand the aerial vehicle.

While the examples discussed herein describe use of the implementationswith an aerial vehicle, such as an unmanned aerial vehicle, it will beappreciated that the described implementations may likewise be used withother vehicles and/or in other scenarios. For example, a plurality ofimaging elements may be positioned on another type of vehicle, such as aground based and/or water based vehicle and an imaging element selectioncontroller utilized to select a combination of imaging elements, asdiscussed above.

FIG. 6 is a block diagram illustrating an example aerial vehicle controlsystem 614. In various examples, the block diagram may be illustrativeof one or more aspects of the aerial vehicle control system 114 that maybe used to implement the various systems and methods discussed hereinand/or to control operation of the aerial vehicles described herein. Inthe illustrated implementation, the aerial vehicle control system 614includes one or more processors 602, coupled to a memory, e.g., anon-transitory computer readable storage medium 620, via an input/output(I/O) interface 610. The aerial vehicle control system 614 may alsoinclude electronic speed controls 604 (ESCs), power supply modules 606,a navigation system 607, and/or a payload engagement controller 612. Insome implementations, the navigation system 607 may include an inertialmeasurement unit (IMU). The aerial vehicle control system 614 may alsoinclude a network interface 616, and one or more input/output devices618.

In various implementations, the aerial vehicle control system 614 may bea uniprocessor system including one processor 602, or a multiprocessorsystem including several processors 602 (e.g., two, four, eight, oranother suitable number). The processor(s) 602 may be any suitableprocessor capable of executing instructions. For example, in variousimplementations, the processor(s) 602 may be general-purpose or embeddedprocessors implementing any of a variety of instruction setarchitectures (ISAs), such as the x86, PowerPC, SPARC, or MIPS ISAs, orany other suitable ISA. In multiprocessor systems, each processor(s) 602may commonly, but not necessarily, implement the same ISA.

The non-transitory computer readable storage medium 620 may beconfigured to store executable instructions, data, flight paths, flightcontrol parameters, and/or data items accessible by the processor(s)602. Data items may include, for example, images obtained from one ormore of the imaging elements, distance information, combined imageinformation (e.g., depth information), etc.

In various implementations, the non-transitory computer readable storagemedium 620 may be implemented using any suitable memory technology, suchas static random access memory (SRAM), synchronous dynamic RAM (SDRAM),nonvolatile/Flash-type memory, or any other type of memory. In theillustrated implementation, program instructions and data implementingdesired functions, such as those described herein, are shown storedwithin the non-transitory computer readable storage medium 620 asprogram instructions 622, data storage 624 and flight controls 626,respectively. In other implementations, program instructions, data,and/or flight controls may be received, sent, or stored upon differenttypes of computer-accessible media, such as non-transitory media, or onsimilar media separate from the non-transitory computer readable storagemedium 620 or the aerial vehicle control system 614. Generally speaking,a non-transitory, computer readable storage medium may include storagemedia or memory media such as magnetic or optical media, e.g., disk orCD/DVD-ROM, coupled to the aerial vehicle control system 614 via the I/Ointerface 610. Program instructions and data stored via a non-transitorycomputer readable medium may be transmitted by transmission media orsignals, such as electrical, electromagnetic, or digital signals, whichmay be conveyed via a communication medium such as a network and/or awireless link, such as may be implemented via the network interface 616.

In one implementation, the I/O interface 610 may be configured tocoordinate I/O traffic between the processor(s) 602, the non-transitorycomputer readable storage medium 620, and any peripheral devices, thenetwork interface 616 or other peripheral interfaces, such asinput/output devices 618. In some implementations, the I/O interface 610may perform any necessary protocol, timing or other data transformationsto convert data signals from one component (e.g., non-transitorycomputer readable storage medium 620) into a format suitable for use byanother component (e.g., processor(s) 602). In some implementations, theI/O interface 610 may include support for devices attached throughvarious types of peripheral buses, such as a variant of the PeripheralComponent Interconnect (PCI) bus standard or the Universal Serial Bus(USB) standard, for example. In some implementations, the function ofthe I/O interface 610 may be split into two or more separate components,such as a north bridge and a south bridge, for example. Also, in someimplementations, some or all of the functionality of the I/O interface610, such as an interface to the non-transitory computer readablestorage medium 620, may be incorporated directly into the processor(s)602.

The ESCs 604 communicate with the navigation system 607 and adjust therotational speed of each lifting motor and/or the thrusting motor tostabilize the UAV and guide the UAV along a determined flight path. Thenavigation system 607 may include a GPS, indoor positioning system(IPS), IMU or other similar systems and/or sensors that can be used tonavigate the UAV 100 to and/or from a location. The payload engagementcontroller 612 communicates with actuator(s) or motor(s) (e.g., a servomotor) used to engage and/or disengage items.

The network interface 616 may be configured to allow data to beexchanged between the aerial vehicle control system 614, other devicesattached to a network, such as other computer systems (e.g., remotecomputing resources), and/or with aerial vehicle control systems ofother UAVs. For example, the network interface 616 may enable wirelesscommunication between the UAV that includes the control system 614 andan aerial vehicle control system that is implemented on one or moreremote computing resources. For wireless communication, an antenna of anUAV or other communication components may be utilized. As anotherexample, the network interface 616 may enable wireless communicationbetween numerous UAVs. In various implementations, the network interface616 may support communication via wireless general data networks, suchas a Wi-Fi network. For example, the network interface 616 may supportcommunication via telecommunications networks, such as cellularcommunication networks, satellite networks, and the like.

Input/output devices 618 may, in some implementations, include one ormore displays, imaging devices, thermal sensors, infrared sensors, timeof flight sensors, accelerometers, pressure sensors, weather sensors,imaging elements (e.g., cameras), gimbals, landing gear, etc. Multipleinput/output devices 618 may be present and controlled by the aerialvehicle control system 614. One or more of these sensors may be utilizedto assist in landing as well as to avoid obstacles during flight.

As shown in FIG. 6, the memory may include program instructions 622,which may be configured to implement the example routines and/orsub-routines described herein. The data storage 624 may include variousdata stores for maintaining data items that may be provided fordetermining flight paths, landing, identifying locations for disengagingitems, engaging/disengaging the thrusting motors, selecting acombination of imaging elements for stereo imaging, etc. In variousimplementations, the parameter values and other data illustrated hereinas being included in one or more data stores may be combined with otherinformation not described or may be partitioned differently into more,fewer, or different data structures. In some implementations, datastores may be physically located in one memory or may be distributedamong two or more memories.

The aerial vehicle control system 614 may also include the imagingelement selection controller 628. As discussed above, the imagingelement selection controller communicates with the plurality of imagingelements and selects combinations of imaging elements for use as astereo pair for generating depth information about an object representedin images obtained by the selected imaging elements. In someimplementations, the imaging element selection controller 628 alsocommunicates with a distance determining element to determine anapproximate distance between the aerial vehicle and a detected object.As discussed above, the approximate distance may be utilized to select acombination of imaging elements based on, for examples, a ratio betweenthe approximate distance and baselines distances between differentcombinations of imaging elements.

Those skilled in the art will appreciate that the aerial vehicle controlsystem 614 is merely illustrative and is not intended to limit the scopeof the present disclosure. In particular, the computing system anddevices may include any combination of hardware or software that canperform the indicated functions. The aerial vehicle control system 614may also be connected to other devices that are not illustrated, orinstead may operate as a stand-alone system. In addition, thefunctionality provided by the illustrated components may, in someimplementations, be combined in fewer components or distributed inadditional components. Similarly, in some implementations, thefunctionality of some of the illustrated components may not be providedand/or other additional functionality may be available.

Those skilled in the art will also appreciate that, while various itemsare illustrated as being stored in memory or storage while being used,these items or portions of them may be transferred between memory andother storage devices for purposes of memory management and dataintegrity. Alternatively, in other implementations, some or all of thesoftware components may execute in memory on another device andcommunicate with the illustrated aerial vehicle control system 614. Someor all of the system components or data structures may also be stored(e.g., as instructions or structured data) on a non-transitory,computer-accessible medium or a portable article to be read by anappropriate drive. In some implementations, instructions stored on acomputer-accessible medium separate from the aerial vehicle controlsystem 614 may be transmitted to the aerial vehicle control system 614via transmission media or signals such as electrical, electromagnetic,or digital signals, conveyed via a communication medium such as awireless link. Various implementations may further include receiving,sending, or storing instructions and/or data implemented in accordancewith the foregoing description upon a computer-accessible medium.Accordingly, the techniques described herein may be practiced with otheraerial vehicle control system configurations.

Although the subject matter has been described in language specific tostructural features and/or methodological acts, it is to be understoodthat the subject matter defined in the appended claims is notnecessarily limited to the specific features or acts described. Rather,the specific features and acts are disclosed as exemplary forms ofimplementing the claims.

What is claimed is:
 1. An aerial vehicle apparatus, comprising: a frame;a plurality of cameras coupled to the frame; a camera selectioncontroller in communication with each of the plurality of cameras, thecamera selection controller configured to at least: during aerialnavigation of the aerial vehicle apparatus: detect an object; determinefirst disparity information associated with a first camera combinationselected from the plurality of cameras; determine second disparityinformation associated with a second camera combination selected fromthe plurality of cameras; determine that the first disparity informationis greater than the second disparity information; select, based at leastin part on a determination that the first disparity information isgreater than the second disparity information, the first cameracombination to monitor the object; and monitor the object using thefirst camera combination, which includes: obtaining a first image fromthe first camera combination; and processing the first image to generatedepth information corresponding to the object.
 2. The aerial vehicleapparatus of claim 1, wherein a first baseline distance associated withthe first camera combination and a second baseline distance associatedwith the second camera combination are different.
 3. The aerial vehicleapparatus of claim 2, wherein the first baseline distance is oriented ina non-parallel arrangement relative to the second baseline distance. 4.The aerial vehicle apparatus of claim 1, wherein the camera selectioncontroller is further configured to at least: determine third disparityinformation associated with a third camera combination selected from theplurality of cameras; and determine that the first disparity informationis greater than the third disparity information.
 5. The aerial vehicleapparatus of claim 1, wherein the camera selection controller is furtherconfigured to at least: determine an approximate distance to the object;select the first camera combination based at least in part on theapproximate distance and a first baseline distance associated with thefirst camera combination; and select the second camera combination basedat least in part on the approximate distance and a second baselinedistance associated with the second camera combination.
 6. The aerialvehicle apparatus of claim 1, wherein the plurality of cameras arespaced about the frame such that each camera pair selected from theplurality of cameras includes a different baseline distance.
 7. Anaerial vehicle apparatus, comprising: a plurality of imaging elementsspaced about the aerial vehicle apparatus; an imaging element selectioncontroller in communication with each of the plurality of imagingelements, the imaging element selection controller configured to atleast: during aerial navigation of the aerial vehicle apparatus: receivedetection of an object; select a first combination of imaging elementsfrom the plurality of imaging elements to monitor the object, whereinselection of the first combination of imaging elements is based at leastin part on first disparity information associated with the firstcombination of imaging elements presenting a greatest disparity; andmonitor the object using the first combination of imaging elements,wherein monitoring the object includes: obtaining a first image from thefirst combination of imaging elements; and processing the first image togenerate depth information corresponding to the object.
 8. The aerialvehicle apparatus of claim 7, wherein the plurality of imaging elementsare spaced about the aerial vehicle apparatus such that each imagingelement pair selected from the plurality of imaging elements includes adifferent baseline distance.
 9. The aerial vehicle apparatus of claim 7,wherein the imaging element selection is further configured to at leastdetermine a first approximate distance to the object, and whereinselection of the first combination of imaging elements is based at leastin part on a ratio of the first approximate distance and a firstbaseline distance associated with the first combination of imagingelements.
 10. The aerial vehicle apparatus of claim 7, wherein aselection of the first combination of imaging elements includes, atleast: determining the first disparity information associated with thefirst combination of imaging elements; determining second disparityinformation associated with a second combination of imaging elementsselected from the plurality of imaging elements; and determining thatthe first disparity information is greater than the second disparityinformation.
 11. The aerial vehicle apparatus of claim 10, wherein theselection of the first combination of imaging elements further includes,at least: determining third disparity information associated with athird combination of imaging elements; and determining that the firstdisparity information is greater than the third disparity information.12. The aerial vehicle apparatus of claim 7, wherein the imaging elementselection controller is further configured to at least: determine asecond approximate distance to the object, wherein the secondapproximate distance is different from a first approximate distance;select a second combination of imaging elements from the plurality ofimaging elements to monitor the object, wherein selection of the secondcombination of imaging elements is based at least in part on seconddisparity information associated with the second combination of imagingelements; and monitor the object using the second combination of imagingelements, wherein monitoring the object includes: obtaining a secondimage from the second combination of imaging elements; and processingthe second image to generate second depth information corresponding tothe object.
 13. The aerial vehicle apparatus of claim 12, wherein thesecond disparity information is greater than the first disparityinformation.
 14. The aerial vehicle apparatus of claim 7, wherein afield of view of each imaging element of the plurality of imagingelements at least partially overlaps with a second view of anotherimaging element from the plurality of imaging elements.
 15. The aerialvehicle apparatus of claim 7, further comprising a distance determiningelement, and the distance determining element performs the detection ofthe object.
 16. The aerial vehicle apparatus of claim 7, wherein thefirst disparity information includes a comparison of correspondingpixels in images obtained by the first combination of imaging elements.17. A method, comprising: during aerial navigation of an aerial vehicle:detecting an object; determining a plurality of combinations of imagingelements from a plurality of imaging elements; for each of the pluralityof combinations of imaging elements, determining a correspondingdisparity information; selecting one combination of imaging elementsfrom the plurality of combinations of imaging elements based at least inpart on the one combination of imaging elements having the greatestcorresponding disparity information; and monitoring the object using theone combination of imaging elements, wherein monitoring the objectincludes: obtaining an image of the object from the one combination ofimaging elements; and processing the image to generate depth informationcorresponding to the object.
 18. The method of claim 17, whereinselecting the one combination of imaging elements includes: determininga first corresponding disparity information for the one combination ofimaging elements; determining a second corresponding disparityinformation for a second combination of imaging elements; anddetermining that the first corresponding disparity information isgreater than the second corresponding disparity information.
 19. Themethod of claim 17, wherein determining the plurality of combinations ofimaging elements is based at least in part on a corresponding baselineassociated with each of the plurality of combinations of imagingelements.
 20. The method of claim 17, further comprising: determining afirst approximate distance to the object, and wherein selecting the onecombination of imaging elements is based at least in part on the firstapproximate distance to the object.